外部流体作用下管道输送流固耦合效应偏移分析

Pipe's offset analysis for a pipeline transporting under action of external fluid considering fluid-solid coupled effects

采用数值方法分析管道结构-外部流体相互耦合效应对管道输送过程中管道自由端偏移的影响。调查中充分考虑管道结构-流体耦合效应,流体域与结构域通过拉格朗日-欧拉公式表述。以垂直悬臂提升管道为研究对象,应用有限元软件ADINA对其外部流体-管道结构进行流固耦合特性研究。研究结果表明:①管道上端不论是采取固接还是铰接支撑,外部流场以不同速度冲击管道时,整个管道偏移变化不明显,在同一流速下对管道偏移变化较为显著的地方集中在管道自由端,最大偏移则出现在自由端顶点处;②管道上端无论是固结还是铰接,随着管外流体速度增加,X方向最大偏移的增量总是小于Y方向最大偏移的增量;而X方向的最小偏移变化量则大于Y方向相应偏移;③同一流速冲击下,固结时Y方向的最小偏移略大于铰接时Y方向的最小偏移,且两者在外部流速为0.3 m/s时出现极大值。

The effects of a pipeline-external fluid interaction on the offset of the free end of the pipe was analyzed with numerical methods,considering a fully coupled fluid-structure interaction（FSI）.The fluid domain and structural domain were described with an arbitrary-Lagrangian-Eulerian（ALE） formulation.A vertical cantilevered lifting pipe was taken as a study object.Its fluid-solid coupled characteristics were studied with the FE software ADINA.The results showed that either its upper end is fixed or hinged,the pipe＇s offset variation is not obvious when the external fluid impacts the piple at different speeds,the maximum offset appears at the free end;with increase in the speed of the external fluid,the maximum offset variation in X-direction is always less than that in Y-direction,the minimum offset variation in X-direction is larger than that in Y-direction;under the impact of the external fluid with the same speed,the minimum offset in Y-direction with the upper end fixed is slightly larger than that with the upper end hinged,both of them become greater when the external fluid speed is 0.3m/sec.